Irving Biederman - US grants

With support from a National Science Major Research Instrumentation Award, Professor Irving Biederman and his colleagues at the University of Southern California will purchase a state of the art three Tesla functional Magnetic Resonance Imaging (fMRI) system for the scientific investigation of how cognitive, emotional, perceptual, memory, linguistic, and motor capacities emerge from activity of the human brain.

Joining Professor Biederman and his Co-PIs Z.-L. Lu, L. Itti, A. Raine, and M. Arbib as users of the fMRI system will be members of a variety of academic units including the Neuroscience Program, the Departments of Psychology, Computer Science, Biology, Gerontology, Biomedical Engineering, Kinesiology, Electrical Engineering, and the House Ear Institute, Currently the community of interested users includes approximately 30 faculty and over 100 graduate and post-doctoral students. This on-campus facility will not only allow these research programs to proceed but will provide the capability for the development of imaging expertise within this community. The magnet will be available to researchers from other institutions as well.

The ability to probe the activity-not just the structure-of the intact human brain has been one of the great methodological advances of neuroscience in the past decade. The instrument will provide high-resolution images of brain structures but its primary use will be to assess functioning of the brain as subjects experience various stimuli or perform various tasks while the system measures neural activity at specific brain loci in the order of a few millimeters. Among the first of the research projects that will be launched once the system is installed is one focusing on regions of the prefrontal cortex known to modulate restraint and an appreciation of the consequences of one's own actions for individuals with and without a propensity for impulsive violence. Other studies are designed to understand how an image of a scene, never perceived previously, could be comprehended in a fraction of a section. Another will assess whether brain-produced opiates in areas that mediate comprehension provide the perceptual and cognitive pleasure associated with novel but interpretable experiences. Another study is motivated by the finding that neurons in monkey cortex involved in the production of certain motor movements, such as grasping, also fire when the monkey views the grasp of another organism. This research will evaluate whether such "mirror" neurons might be the core imitative capacity fundamental to the evolution of language. Still another investigation will focus on where and how "episodic memory"-the mental diaries of our lives-are produced and stored in the brain.

Plans for the operation of the magnet, to be housed in the Dana and David Dornsife Cognitive Neuroscience Imaging Center, will include instructional courses designed to give hands-on training and research experience to undergraduate as well as graduate students.
Special outreach programs are designed to involve qualified high school students from the local community as part of an effort to provide opportunities for underrepresented minorities to be counted among the next generation of scientists advancing our knowledge of cognitive and behavioral neuroscience.

In a fraction of a second-in a single glance-we comprehend complex scenes never encountered previously. What is the basis of this extraordinary capacity? A prominent theory of shape recognition holds that objects exist in memory as an arrangement of simple, regular, 2D and 3D geometrical shapes, such as bricks, cones, cylinders, wedges, circles, and squares. To see a novel scene is to make contact with these pre-prepared elementary shapes in memory, called geons. How does this extraordinary capacity arise? By one hypothesis, a rich early experience with natural extended contours would be sufficient. An alternative hypothesis is that geons derives from our early experience immersed in the geometry of a manufactured world. Would individuals from a culture with only minimal exposure to manufactured-world artifacts show the same kinds of perception as artifact-immersed college students? Would they, instead, have greater sensitivity for distinguishing among highly irregular shapes, such as bushes, clouds, or mountain ridges?
Dr. Biederman and Marissa Nederhouser, M.A., will answer the latter questions in an investigation of shape discrimination by the Himba. The Himba are a semi-nomadic tribe in northern Namibia with minimal exposure to Western artifacts and a language that contains none of the terms for simple shapes (such as those listed for some of the geons). Ms. Nederhouser will be joining a British team studying color and linguistic discriminations. There is some urgency in this research because the Namibian government will soon expand tourism to this remote area, with the consequent increase of exposure to manufactured-world artifacts. Broader impacts of this research include a better understanding of natural diversity in a fundamental mental capability.

In a fraction of a second, an image of an object or scene--one never experienced previously--can be easily comprehended by a human observer. The functional magnetic resonance imaging (fMRI) study of the neural basis of this remarkable feat has been greatly advanced by the discovery of a cortical area that responds well to intact objects but not to scrambled versions of these same images. This region, termed "the lateral occipital complex" (LOC), runs ventrally from the occipital lobe to the posterior regions of the temporal lobe. LOC is not merely activated by familiar objects in that unfamiliar objects, such as abstract sculptures, also produced greater activation in LOC compared to their scrambled versions. Nor is activation in LOC merely a feed forward effect from earlier visual stages in that these stages show greater activation for the scrambled compared to the intact versions of the images. LOC responds equivalently to a photograph and a line drawing of the same object. Bilateral lesions to LOC have been shown to produce a complete inability to recognize objects on the basis of their shape, while leaving visually guided motor interactions unaffected. LOC thus represents physical shape to which, presumably, semantic information, including a name, can be associated. This stage thus appears to be at the threshold of cognition. Despite the advances enabled by the LOC localizer, there is considerable uncertainty as what this localizer is actually localizing. The scrambling operation affects both low-level measures of the image as well as higher-level aspects associated with the interpretation of the object. The low-level measures include an increase in the extent of the display produced by the scattering of the elements, a loss of low frequency information, and a marked increase in the clumps from one (the intact object) to over 20. Of course, with the scattering, the sizes of the clumps are similarly reduced. With National Science Foundation funding, Dr. Irving Biederman will conduct fMRI research designed to clarify just what the localizer is localizing and in doing so, provide some clues as to how shape is abstracted from an image. The research would elucidate the neural coding of object vs. texture, the effect of the number of elements in a display and whether these elements comprise an intact object or scene. Additionally, attention will be paid toward defining those cortical areas that might be more responsive to aspects, such as texture rather than object, in the scrambled images.

The immediate broader impacts will be to contribute to advancing our knowledge as to the neural representation of shape for purposes of recognition. The research will fill a critical gap between psychophysical (behavioral) research on object recognition and single-unit recording of shape variations in the macaque. Although the homologues between human and macaque of primary sensory and motor cortices are well established there are significant questions concerning the homologues of later, perceptual "association" areas. Extensive plans are already in place for an outreach program involving USC's NSF-funded 3T scanner. Because of the accessibility of the problem of real-time object recognition to a non-technically advanced audience, this research will be one of the featured research projects for exposing cognitive neuroscience to students from USC's largely minority neighborhood and to recruit some to participate in the research itself.

In a fraction of a second a human observer can easily comprehend an image of an object or scene that has never been encountered before. Knowledge of the neural basis of this remarkable ability has been advanced by the discovery of a cortical area that is activated by the shape of intact objects but not by scrambled versions of these same images. This brain region, termed the lateral occipital complex (LOC), is activated in functional magnetic resonance imaging (fMRI) studies by both familiar and unfamiliar objects. The LOC is also activated by both photographs and line drawings of the same object, indicating that the surface qualities are represented elsewhere. And, bilateral lesions to LOC have been shown to produce a complete inability to recognize objects on the basis of their shape. LOC thus represents physical shape to which, presumably, semantic information, including a name, can be associated. With support from the National Science Foundation, Dr. Irving Biederman and colleagues at the University of Southern California will conduct a series of experiments that aim to better determine how shape is represented in the LOC. One project will test whether parts and relations have distinguishable neural loci. Other projects will assess whether the coding of shape in the LOC is accomplished in terms of local image features, parts, global shape or concepts, and the locus and extent to which invariant coding of shape - which allows an object to be recognized as unchanged even when it is viewed at a different position in the visual field, at a different size, at a different orientation, or lit from a different direction - is manifested in LOC.

This research will fill a critical gap between human psychophysical research on object recognition and work on single-neuron recordings in response shape variations that have been performed in non-human primates. Although the homologues between human and non-human primate primary sensory and motor cortices are well established there are significant questions concerning the homologues of later, perceptual association areas. Perhaps the most important potential impact of the proposed research is that it could allow us to understand the neural representations that subserve not only object recognition but cognition more generally.